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It is also safe because technically a > no-op. > > Signed-off-by: Alexandre Courbot > --- > rust/kernel/transmute.rs | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/rust/kernel/transmute.rs b/rust/kernel/transmute.rs > index be5dbf3829e2..8d78c81e3749 100644 > --- a/rust/kernel/transmute.rs > +++ b/rust/kernel/transmute.rs > @@ -170,6 +170,9 @@ macro_rules! impl_frombytes { > } > > impl_frombytes! { > + // SAFETY: This type is empty and thus does not consume any data. > + (), I'd avoid use the word "empty" as it has the meaning of uninhabited types (never type) in type theory. ZSTs that are inhabited are unit types (or singletons). Perhaps better to have a justification that applies to all inhabited ZSTs that don't have special semantics. Something like this? // SAFETY: Inhabited ZSTs only have one possible bit pattern. (), {} PhantomData, Best, Gary > + > // SAFETY: All bit patterns are acceptable values of the types below. > u8, u16, u32, u64, usize, > i8, i16, i32, i64, isize, > @@ -230,6 +233,9 @@ macro_rules! impl_asbytes { > } > > impl_asbytes! { > + // SAFETY: This type is empty and thus returns an empty slice. > + (), > + > // SAFETY: Instances of the following types have no uninitialized portions. > u8, u16, u32, u64, usize, > i8, i16, i32, i64, isize, >